1. Field of the Invention
The present invention relates to a method of using data, mainly content data such as image data, sound data, or text data, a data processor, and a computer usable medium.
In order to prevent copycat or piracy of computer program or content data recorded on a recording medium such as a CD-ROM, and to promote correct use, a various cryptographic keys are used to scramble the data. Since data quantity is increasing rapidly along with development of multimedia, it is important to perform the scrambling process efficiently so as to promote correct use.
2. Description of the Prior Art
Conventionally, a cryptographic key has been used to scramble data for correct use of the data that are, e.g., programs or content data, supplied by the recording medium such as a CD-ROM. The cryptographic key for descrambling is sent from a data provider to a user who requested to use the data, via telephone or communication, for example. In this case, the data provider performs a process for charging the user, if necessary.
It is often performed to record two kinds of data, a sample version (or a demo version) and a product version, on one recording medium for providing them. In this case, the provider may scramble the product version, but not scramble the sample version, when recording. The user can use the sample version freely, but have to get the cryptographic key for descrambling at some cost so as to use the product version.
The conventional method has a disadvantage in that data quantity is increased since two kinds of data are recorded overlapping, the sample version without being scrambled and the product version with being scrambled. Therefore, quantity of contents or programs that can be recorded on the recording medium becomes small, resulting in high cost.
In addition, if not only the simple two kinds of license levels including the sample version and the product version, but more kinds of license levels are used for providing data, the quantity of data may increase more since each kind of data should be recorded.
The object of the present invention is to enable restricting the use of data in accordance with plural license levels without increasing the quantity of data as the conventional method, and to promote of correct use of the data.
According to a first aspect of the present invention, a method of using data by a data processor is provided. As shown in FIGS. 1-6, a series of data DT is recorded over plural sections BK that can be managed on the recording medium ST. The method includes the steps of storing plural kinds of link information L for designating one or more sections BK of the data DT that enables the use in the recording medium ST in accordance with license levels, and enabling the use of the link information L corresponding to the license level that was selected by a user.
According to a second aspect of the present invention, the method further includes the step of enabling the use of the link information L corresponding to the license level that was selected by a user, and enabling a provider of the data DT to do charge process in accordance with the license level.
According to a third aspect of the present invention, the data DT recorded on the recording medium ST is scrambled by a first cryptographic key K1.
According to a fourth aspect of the present invention, there are provided two license levels which are the licensed and non-licensed, and the link information LA corresponding to the licensed is scrambled by a second cryptographic key K2.
According to a fifth aspect of the present invention, the second cryptographic key K2 is recorded on the recording medium ST, and the use of the second cryptographic key K2 is permitted when the correct password is input to the data processor.
According to a sixth aspect of the present invention, an application program AP1 recorded on the recording medium ST controls so as to output the contents of the data DT recorded on the section BK designated by the selected link information L from the data processor when the correct user ID is input to the data processor.
According to a seventh aspect of the present invention, another method of using data by a data processor is provided. Series of data DT are scrambled by a first cryptographic key K1 and are recorded over plural sections BK that can be managed on the recording medium ST. The method includes the steps of storing plural kinds of link information L for designating one or more sections BK of the data DT that enables the use in the recording medium ST in accordance with license levels, performing charge process to a user in accordance with the license level selected by the user, permitting the user to get the first cryptographic key K1 so that the data processor can decode the data DT, and outputting the contents of the data DT from the data processor using the link information L corresponding to the selected license level.
According to an eighth aspect of the present invention, a data processor is provided for using a series of data DT recorded over plural sections BK that can be managed on a recording medium ST. The data processor includes link information storage means 10a for storing the link information L for designating one or more sections BK of the data DT that enables the use, selection input means 13, 14 for selecting a license level, and means for outputting the contents of the data DT using the link information L corresponding to the selected license level.
According to a ninth aspect of the present invention, a recording medium is provided, on which a series of data DT is recorded over plural sections BK that can be managed so that the data processor can use the data. The recording medium stores plural kinds of link information L for designating one or more sections BK of the data DT that enables the use, in accordance with license levels.
According to a tenth aspect of the present invention, a computer usable medium is provided. On the computer usable medium, a series of data is recorded over plural sections BK that can be managed so that the data processor can use the data. The computer usable medium stores plural kinds of link information L for designating one or more sections BK of the data DT that enables the use in accordance with license levels, a display control program AP1 for displaying a selection input picture HG1 used for selecting a license level, and an output processing program AP1 for outputting the contents of the data DT using the link information L corresponding to the selected license level.